We have previously described a form of electronic book in our earlier applications PCT/GB2006/050235 and GB 0702347.6, hereby incorporated by reference.
Background prior art relating to electronic document reading devices can be found in U.S. Pat. No. 6,124,851, US2004/0201633, US2006/0133664, US2006/0125802, US2006/0139308, US2006/0077190, US2005/0260551, U.S. Pat. No. 6,124,851, U.S. Pat. No. 6,021,306, US2005/0151742, and US2006/0119615.
There are many different file formats in use by software on Personal Computers today and a huge number of programs to process those files. When the need arises to display the contents of those files on a device other than a PC, there is a problem.
Often the file format is proprietary and hence closed to outside developers. Sometimes, even if the format is known, the data is so rich and complex that unless the device has the processing power of a modem PC, it can take a long time to process and render the document.
In an electronic reader type device, typically in order to operate as a portable light-weight unit running from batteries there are significant compromises on processing power available. These devices will typically not run the same software as desktop computers.
This has several problems: even a moderately complex office document can take minutes to process, unacceptable from a usability perspective; the supported formats are limited to these which are popular; and adding new file formats requires updating the device firmware.
A solution is to utilise another system to process the files there are examples of such systems but these have significant problems: in order to create a simpler format, they will throw away anything that requires complex processing; if the service is on the Internet, then in order to reduce bandwidth complex images are downgraded to a poor quality; usually, the intermediate format is another proprietary closed format; and they are limited to a known set of file formats, typically only the very popular formats, and these need updating as new versions of those formats are introduced.
For a device that is designed to take documents away from say a PC or other consumer electronic device in a portable fashion, for reading elsewhere, these problems form a major barrier.